Every Little Thing
by SkyGem
Summary: There's something off with All Might. Ever since that fateful fight with All for One - or rather…no, maybe a few days before that? He'd shown up to work one day, looking disoriented, almost lost, and when he'd laid eyes on Sir, a small, choked little sob had escaped him, and he'd swept his sidekick into a crushing hug. Time travel fix-it.
1. Is Gonna Be Alright

There's something off with All Might. He knows it as surely as he knows the sky is blue and the Earth is round.

He's tried asking All Might what the problem is, but every time his concerns are deflected with the same bright smile, and an airy "I'm fine!"

Normally, Sir wouldn't pay it any mind - All Might is an adult after all, and can usually take care of himself. If he had wanted Sir's help, he would have asked for it. But it's been over a month, and All Might doesn't seem to have gotten any better in that time.

Ever since that fateful fight with All for One - or rather…no, maybe a few days before that? He'd shown up to work one day, looking disoriented, almost lost, and when he'd laid eyes on Sir, a small, choked little sob had escaped him, and he'd swept his sidekick into a crushing hug.

He'd had multiple close calls with his quirk that day, constantly using either too much or too little force - almost as if he had forgotten just how strong he was.

His control over One for All had improved rapidly over the course of the day, but that lost, disoriented look didn't leave him.

Even now, he'll sometimes look down at his side, as if to speak to someone much shorter than him, but then he'll catch himself when he sees no one there, and for a split second, his face will fall into an expression of utter devastation. Those moments are always hardest for Sir, because he never knows what to do to make the hurt go away.

He spends hours upon hours trying to think of ways to help bring All Might out of his slump but in the end, the answer to all his questions comes to him in the form of a 9-year-old kid with messy green curls and freckles dotting his cheeks.

They've just taken down yet another villain, and while All Might stays behind to talk to the press, Sir decides to return to their agency to warm up their lunch.

Only, as soon as he walks into the lobby of their agency, the first thing that catches his eye is the kid standing on his tippy toes to look over the front desk, arguing with the poor, hassled-looking secretary.

"-just need to see him _once_! I promise I won't be a nuisance!" the child is whining, and there's something like real desperation in his voice, making Sir draw up short.

The child turns to look back then, perhaps having heard the door open and close, and his brilliant green eyes open wide in a shocked expression that sends a shiver of familiarity creeping up Sir's spine - it's the same expression All Might had turned on him that day over a month ago.

"Sir!" the child gasps, taking a halting step forward, arms reaching out as if to embrace. But then something seems to click in his mind, and he cringes back, drawing his arms back tightly around himself.

There are tears shining in his eyes, and his lower lip is trembling, and Sir can't help but think that he is so completely out of his depth right now - All Might is the one that usually deals with crying children.

"And just what are you doing here, young man?" asks Sir, trying to soften his usual glare into something a little more child friendly.

The child fidgets, casting his gaze to the floor. "I-I need to see All Might for something important," he murmurs, and it's basically exactly what Sir had expected.

"He'll be returning in a few minutes," Sir replies, and the child's eyes fly up to meet his gaze, a small noise of delight escaping from the child.

He's kind of absolutely adorable, and Sir fully expects All Might to be completely head over heels for the child immediately upon meeting him - All Might had always had a weak spot for children, and perhaps if he hadn't been the number one hero, perhaps if his position as the Symbol of Peace hadn't put a giant target on his back, he would have had a beautiful young wife and several children by now.

But life isn't fair, and Sir knows that All Might will probably live out the rest of his days as a bachelor.

The child opens his mouth, perhaps to ask a question, but immediately snaps it shut as Sir hears the automatic doors swish open behind him, and feels the looming presence of his partner behind him.

The child's eyes widen; the tears are back in full force, along with the tremble in his lip. He takes a stuttering step forward, and he looks to be maybe a second away from breaking down.

He opens his mouth to say something, but All Might ends up beating him to it.

"Midoriya shounen," he gasps, and Sir whips his head around, shock spreading through him as he sees the expression on his partner's face - something of a mix between fragile hope, and complete, unconditional adoration.

That seems to be the last straw, as the child's face crumples and a sob tears out of his throat.

He takes one step forward, then another, before dashing forward into All Might's waiting embrace. The hero sweeps him up in gentle arms, one giant hand coming up to cradle the child's head as he sobs into All Might's neck, small hands clutching tightly at the fabric of his shirt.

"All M-Miiiight," the child hiccups, "Y-you're mine, right? You're my All Might? You remember me? I-I-I'm not alone?"

"Of course I remember you, my boy," All Might responds, his voice hitching with emotion. He continues to reassure the child in his arms in a quiet, soothing voice too quiet for Sir to make out his words.

"W-what about Sensei?" the child whispers, voice fearful. "Y-you fought him already, right? D-did he hurt you? I-is he-?"

"He's gone," All Might answers, fingers carding through messy green curls. "For good this time. I made sure of it. Everything is going to be okay."

"B-but what about Shigaraki? A-and senpai? And-?"

"Safe," All Might reassures. "They're all going to be okay, my son. You and I, we're going to make sure of it. You hear me?"

The child responds, but Sir doesn't hear a word of what he says.

 _Son._

The word clangs around his head, the implications of it deafening. There are so many things Sir wants to ask, so many things he needs to know. But for now, he decides to take his leave, allowing the father and son to continue their reunion in peace.

There will be time for questions later.


	2. A Future Undone

"Izuku!"

The frantic voice belongs to a short, plump woman who's just come running into the agency, her long green hair disheveled, her eyes wide with worry.

It's not hard to figure out that she's the child's (Izuku's?) mother, and the moment she sees her son in All Might's arms, she seems to calm down greatly.

All Might has turned to stare at her, and is now frozen with indecision, the child still in his arms.

The woman takes a moment to catalog everything she's seeing, and finally, she seems to come to a conclusion.

"All Might…so you remember everything too?"

And All Might, normally so good at controlling his expression, actually looks surprised at that.

"You too…?" he asks the woman.

And she chuckles quietly.

"Not at all," she says, looking almost regretful. "But I noticed Izuku start acting strangely about a month ago, and managed to convince him to tell me everything. I have to say, I was a little skeptical at first, but it was the only explanation that made sense."

All Might laughs in response. "Well, I suppose I should have guessed. Izuku here is good at a great many things, but acting has never been one of them."

His expression is equal parts amused and proud as he looks down at the nine-year-old still in his arms, but that doesn't stop the squawk of outrage from his son(?) at the jibe.

"I'll have you know I'm a _perfectly good_ actor!" the child declares in mock outrage, face settling into an adorable pout. "I just didn't want to lie to mom."

"But of course," All Might replies indulgently, leaning in to press a quick kiss to the child's forehead, effectively erasing the displeasure from his face.

"As heartwarming as this all is," Sir finally interrupts, drawing everyone's eyes to him. "I believe we should probably head up to your office, All Might, before discussing anything further, lest anyone overhear what I am sure is going to be a very _interesting_ conversation."

He stares straight at his partner as he says this, an eyebrow raised, expression challenging, as if daring All Might to try and exclude him from the conversation ahead.

But All Might doesn't even miss a beat as he smiles brightly back at Sir, replying that, "Of course, of course! Come, let us go on upstairs, and we can discuss this over lunch."

Izuku nods eagerly, bouncing excitedly in All Might's arms. And sure he's mine, and more than capable of walking by himself, but he seems quite content to stay as close to All Might as possible.

His mother, however, is staring at Sir a little guardedly, unsure if he can be trusted with what is obviously a closely guarded secret. But since her son and husband(?) seem to trust Sir, she eventually gives in and follows them to the elevator.

All Might and Sir's agency isn't a particularly big one - with only one sidekick and a couple of management employees, two floors and a couple of office rooms are more than enough for them all to make do.

They pass a couple of people on their way to All Might's office, earning shocked stares from everyone that sees them.

Izuku smiles and chirps out greetings to all of them, waving enthusiastically. He gets only 2 responses, but that doesn't seem to deter him.

Sir, for one, is glad that All Might's office is soundproof - their employees are usually pretty good about respecting boundaries, but he just knows that they're all going to be pressed up against the doors, trying to hear the conversation going on inside.

It takes them another ten minutes or so to warm up their food and get settled around All Might's desk, but finally the conversation begins, and the first thing All Might says is- "Izuku and I are from the future."

Sir blinks a few times at the suddenness, but ends up taking the revelation with minimal confusion and skepticism. Having a quirk like foresight means that talk of the future isn't too out of the ordinary for Sir, and more than that, he knows that All Might isn't the kind to lie - ergo, he must be telling the truth.

"I…see," he says finally, once he's able to gather his thoughts once more. "Continue."

Working seamlessly, All Might and Izuku take turns telling him about the gruesome future they had lived - about All for One injuring All Might so badly in their fight that he lost his lung and stomach, about Izuku inheriting One for All, about the League of Villains attacking USJ, about the Stain incident and the Kamino Ward tragedy and the Eight Precepts and on and on and on until Sir thinks hes going to throw up. The knowledge of his own death is _nothing_ in the light of all the things the sweet little child in front of him has gone through.

Finally, All Might falls silent, and Sir knows that they're nearing the end of the tale.

Whatever brought these two into the past seems to be centered on little Izuku, the future symbol of peace.

"I think it's a part of One for All," he says quietly. "Maybe it was the quirk of one of the previous users that merged with One for All and was passed down without any of us knowing about it."

He looks up at Sir, and his eyes are haunted, glassy with unshed tears.

"I saw them die," he says, and his voice hitches. "We were able to defeat the League of Villains, but _everyone_ died. My classmates" - a sob escapes him, and his voice gets quieter - "my teachers" - tears drip down his cheeks and onto the clenched fists in his lap - "my parents" - All Might and the child's mother both lean over to comfort him, wrapping him in a warm embrace.

He takes a moment to compose himself.

"I was all by myself, and I didn't want to be. What's the point of being a hero if you couldn't save _anyone_? And maybe there are certain circumstances needed for it to happen, maybe your world needs to be ending, maybe there needs to be no way to fix it, maybe you need to _want_ to change things so badly that you'll go mad if you can't, but I passed out from exhaustion, or maybe blood loss, and the next time I woke up, I was in my bed at home, more than a decade in the past."

There's silence in the office for a long time after that, the food forgotten, All Might and Izuku's mother still holding him.

Sir tries to think of something to say, but once again, Izuku beats him to it.

The child takes a deep breath, wipes the tears from his face, and looks up at Sir with red-rimmed eyes and a brilliant smile spreading slowly across his lips.

"But this time is going to be different!" he assures. "We're going to make sure none of it happens and everything is going to be okay! Because I AM HERE!"


	3. A Sudden Decision

Sir smiles down at the 9-year-old.

"I'm sure," he says, not unkindly.

Izuku returns the smile, all traces of the haunted warrior from before suddenly gone, replaced once again by the cheerful child that seems to be Izuku's natural state of being.

There's relative quiet in the room for a few minutes more as its occupants go back to eating their now cold food.

Sir is the one that breaks the silence this time, as a thought suddenly occurs to him.

"You said you were quirkless?" he asks Izuku, and receives a nod in return. "Then how are you so sure that the power that sent you to the past is a part of One for All? Could it not have been an undiscovered quirk that you were born with? After all, it doesn't happen often, but it is not entirely unheard of for a child born with an extra joint in their pinky toe to still develop a quirk."

Izuku is shaking his head even before Sir has finished speaking.

"I thought of that possibility too," he says, "But then it wouldn't explain All Might."

Sir's eyes narrow in confusion, but after a few moments of thought, he suddenly understands.

"The two of you are the only ones with memories of the future," Sir says, and earns a nod from Izuku.

"If it had been a quirk that I was born with, then I would probably have been the only one with memories of the future, or at least if I was able to give the memories to other people, then All Might wouldn't be the only one I couldn't give them to. So the power is probably a part of One for All, and the reason All Might remembers is because he's the current holder of it."

"Makes sense," Sir replies. And then, because he's been wondering it for a while now and figures now's as good a time as any, he asks, "So, why are you still calling your father by his hero name?"

This seemingly innocent question gets interesting reactions out of all three of his companions, causing All Might to almost choke on his spit.

Sir raises an eyebrow, unimpressed, and waits until the three of them get themselves back under control.

Izuku laughs awkwardly, saying, "That's…kinda of a complicated matter. All Might isn't…technically…my dad…in this timeline…?"

"In this timeline?" Sir asks, confused.

Izuku looks at All Might beseechingly, and the hero answers for him, saying that, "I am not his biological father."

Sir makes a noise of understanding, and things start to click into place in his mind.

"In the future timeline, Inko-san and I married in young Izuku's third year of high school, and so I am not yet Izuku's father…legally."

"Yet?" asks Izuku's mother (Inko?) quietly, looking somewhat surprised, and All Might's face immediately turns beet red.

"Not that it _has_ to happen at all!" he is quick to reassure, turning an awkward smile upon the woman that might once have been his wife. "I would be disappointed, of course, but I understand that you do not have any memories of the times we spent together…or would have spent together, I suppose. So please, I hope you would not feel under any obligation to become romantically involved with me. All I ask is that I still be allowed to continue seeing our… _your_ son," All Might continues, and he sounds so desperate near the end, his voice borderline miserable as he corrects himself.

Izuku looks back and forth between his parents with a distressed expression, and though Sir knows that mentally he is already an adult, in that second, he looks exactly like the 9-year-old whose body he inhabits. He leans in close to All Might, wrapping an arm tightly around the man as if worried he'll be bodily pried away from him.

Inko just huffs out an exasperated little chuckle at his actions.

"Oh, you ridiculous men," she teases, reaching out to push Izuku's heavy black curls out of his eyes before turning an amused smile on the number one hero. "Even if I wasn't married to you in an alternate timeline, do you honestly think I could, in good conscience, forbid Izuku from seeing you after he's admired you all his life?"

All Might doesn't seem to know how to respond to that.

"And besides," she continues before he can come up with anything, "If I really did end up loving you in this future timeline as much as Izuku tells me I did…I don't think I'd mind giving our relationship a chance."

All Might perks up then, a blinding smile spreading across his face. "Really?" he asks, delighted. And he looks so hopeful, so much happier than Sir remembers ever seeing him.

And even if everything still went to shit, even if they didn't end up being able to save everyone, even if Sir did still end up dying…it would still be worth it, he thinks. Just to see that pure, genuine and uncomplicated joy on All Might's face.

* * *

The next few months after that seem to positively fly by.

Little Izuku soon becomes a common sight around the agency, and though their other employees still don't know who exactly he is, Sir knows that they've all become unbearably fond of the mischievous, friendly little child.

He and his mother live a bit far from the agency for Izuku to visit during the school week, but he always, inevitably, turns up at their doorstep on Friday evenings, his little overnight bag in tow. Like clockwork, he'll come trotting through the lobby at exactly seven in the evening, greeting the secretary cheerily before tearing up the stairs to the second floor to deposit his bag in the lounge, and get started on his homework while he waits for Sir and his father to return from their patrol.

Sometimes, Inko will come along with her son on Fridays, but sometimes her work will require her to stay behind and make the trip on the next day. Either way, the two of them will spend their weekends in Tokyo, and when they inevitably have to return to Musutafu on Sunday evening, the two are seen off by the tearful employees at All Might's agency, urging Izuku to come play again next week.

Izuku happily indulges the employees in their theatrics, always greeting each of them by name, with bright smiles and warm hugs.

This peaceful routine continues for approximately three months, until All Might casually drops a bomb on Sir one day over lunch.

"Inko and I have decided to get married."


End file.
